3-DIMENSIONAL NUMERICAL-SIMULATION OF PERIODIC NATURAL-CONVECTION IN A DIFFERENTIALLY HEATED CUBICAL ENCLOSURE

A high-resolution, finite-difference numerical study is carried out of three-dimensional unsteady periodic natural convection of air in a cubical enclosure at the Rayleigh number of 8.5 x 10(6). The enclosure is subjected to differential heating at the two vertical side walls. The other vertical walls are insulated. A linear temperature profile is specified at the thermally-conducting horizontal walls. Flow details in the three-dimensional field are captured by elaborate post-processing of the computational results, for which the state-of-the-art numerical visualization techniques are utilized. The three-dimensionality of the mean flow fields is observed to be confined into narrow regions near the end walls. The time-dependent solutions clearly indicate the periodic nature of the flow. The oscillation frequency is in close agreement with the previous experimental measurements reported in the literature.